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In cases of confirmed cervical stenosis, mechanical dilatation of the cervix under general anesthesia has been tried to make subsequent ET easier. This has been tried either as an interval procedure (at the start of the IVF cycle) [6,11], or at the time of the oocyte retrieval [4,12]. Both have been associated with easier subsequent ET, but only interval dilatation has led to improvement in pregnancy rate, perhaps because it allows sufficient time for the endometrium to recover from any trauma, inflammation or bacterial contamination resulting from the dilatation at the time of oocyte retrieval [13].

Other reported methods involve the use of osmotic cervical dilatation. These include the use of hygroscopic cervical rods (Dilapan) inserted in the cervix for 4 hours early (day 4) in the stimulation phase [14], and the use of intracervical laminaria tents for 24 hours – either at oocyte retrieval [5] or early in the stimulation phase [13]. All have been associated with easier ET and pregnancies, but the reported numbers are too small to allow for a meaningful comparison amongst different methods. These methods allow cervical dilatation on an outpatient basis without the need for general anesthesia.